Door-spring.



0'. KATZEN-BERBEH.

DOOR SPRING. APPLICATION FILED JULY 22..19:s.

' Patent/9d Dec. 4,1917.

IIVVENTOR Oscm" Yufizenbev ev WITNESSES A TTOR/VEVS Parana onmon.

OSCAR KA'IZENBERGER, OF CHICAGO, ILLINOIS.

DOOR-SPRING.

Specification of Letters Patent.

Patented Dec. a, 1917.

Application filed July 22, 1916. Serial No. 110,672.

proved Door-Spring, of which the following 7 is a full, clear, and exact description.

This invention relates to door springs and has for an obiect the provision of an improved construction whereby a spring may be wound but cannot be wound to an undesirable extent.

A further object more specifically is the provision-of a Winding member for a door spring and a stop or lug projecting therefrom for limiting the rotary. movement thereof.

In the accompanying drawings Figure 1 is a plan view of a spring shown in position, the same disclosing an embodiment of the invention.

Fig. 2 isa sectional view through Fig. 1 on line 22, the same being on an enlarged scale with certain parts broken away.

Referring to the accompanying drawingby numerals, 1 indicates a door frame of any desired kind and 2 a door, the frame 1 having a plate 3 secured thereto in any suitable manner to which one end of a spring is secured, the opposite end being secured to the extension 5 of the winding plate 6. The extension 5 projects through the upstanding Wall 7 of a bracket 8 rigidly secured in any suitable manner to door 2. In this class of door springs it is usually arranged to apply the spring and then wind the spring after 1t the desired extent, after which the pin 10 is placed in position for preventing unwinding and also for causing the transmission of tension from'the spring to the brackets 8 and from thence to door 9..

In case a person attempts to wind the spring for too great a distance the lug or projection 12 will strike against the bracket 8, as shown in dotted lines in Fig. 2, and thus limit the winding action. The lug 12 may be formed integral with the plate 6 or may be made separate and rigidly secured thereto in.

any desired way. It will be observed that the lug 12 will not in any way interfere with the winding of the spring but will prevent the spring from being wound beyond an undesirable extent. In addition to preventing the spring being over-tensioned, the same feature embodied on the tension lug also prevents the spring from being wound in the wrong direction, or, rather, unwound.

What I claim is:

A door spring, comprising two brackets, one of the brackets having an apertured member, and provided with a stop adjacent said member, a plate-like winding member having a cylindrical projection extending through and turning in the aperture of the member of the bracket, said winding member being adjacent the apertured member and provided with radial apertures and a radial lug, said lug lyingin the plane of said member and adapted when the said member is turned in one direction to engage the bracket and to engage the stop when said member is turned in the opposite direction, a spring secured to one bracket and to the extension of the winding member, and a pin in an aperture of the winding member and engaging the stop of the bracket, whereby the spring is prevented from being overtensioned or wound in the wrong d rection.

OSCAR KATZENBERGER.

Witnesses:

OLGA LUND, E. J. HOSKINS.

Copies of this patent may be obtained for five cents each. by addressing the "Commissioner of Patenta,

' Washington, D. C. 

